/*      $NetBSD: in6_print.c,v 1.1 2014/12/02 19:36:58 christos Exp $   */

/*-
 * Copyright (c) 2014 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
#include <sys/cdefs.h>

#include <sys/types.h>
#ifdef _KERNEL
__KERNEL_RCSID(0, "$NetBSD: in6_print.c,v 1.1 2014/12/02 19:36:58 christos Exp $");
#include <sys/systm.h>
#else
__RCSID("$NetBSD: in6_print.c,v 1.1 2014/12/02 19:36:58 christos Exp $");
#include <stdio.h>
#define s6_addr32 __u6_addr.__u6_addr32
static const uint8_t hexdigits[] = "0123456789abcdef";
#endif

#include <netinet/in.h>

int
in6_print(char *buf, size_t len, const struct in6_addr *ia6)
{
        int i;
        char *bp;
        char *cp, *ecp;
        const uint16_t *a;
        const uint8_t *d;
        int dcolon = 0;

        if (IN6_IS_ADDR_V4MAPPED(ia6)) {
                char buf4[INET_ADDRSTRLEN];
                struct in_addr ia = { .s_addr = ia6->s6_addr32[3] };
                in_print(buf4, sizeof(buf4), &ia);
                return snprintf(buf, len, "::ffff:%s", buf4);
        }

#define ADDC(c) do { \
                if (cp >= ecp) {\
                        cp++; \
                } else \
                        *cp++ = (char)(c); \
        } while (/*CONSTCOND*/0)
#define ADDX(v) do { \
                uint8_t n = hexdigits[(v)]; \
                ADDC(n); \
                if (cp == bp && n == '0') \
                        cp--; \
        } while (/*CONSTCOND*/0)

        cp = buf;
        ecp = buf + len;
        a = (const uint16_t *)ia6;
        for (i = 0; i < 8; i++) {
                if (dcolon == 1) {
                        if (*a == 0) {
                                if (i == 7)
                                        ADDC(':');
                                a++;
                                continue;
                        } else
                                dcolon = 2;
                }
                if (*a == 0) {
                        if (dcolon == 0 && *(a + 1) == 0) {
                                if (i == 0)
                                        ADDC(':');
                                ADDC(':');
                                dcolon = 1;
                        } else {
                                ADDC('0');
                                ADDC(':');
                        }
                        a++;
                        continue;
                }
                d = (const u_char *)a;
                bp = cp + 1;

                ADDX((u_int)*d >> 4);
                ADDX(*d & 0xf);
                d++;
                ADDX((u_int)*d >> 4);
                ADDX(*d & 0xf);
                ADDC(':');
                a++;
        }
        if (cp > buf)
                --cp;
        if (ecp > buf) {
                if (cp < ecp)
                        *cp = '\0';
                else
                        *--ecp = '\0';
        }
        return (int)(cp - buf);
}

int
sin6_print(char *buf, size_t len, const void *v)
{
        const struct sockaddr_in6 *sin6 = v;
        const struct in6_addr *ia6 = &sin6->sin6_addr;
        char abuf[INET6_ADDRSTRLEN];

        if (!sin6->sin6_port)
                return in6_print(buf, len, ia6);
        in6_print(abuf, sizeof(abuf), ia6);
        return snprintf(buf, len, "[%s]:%hu", abuf, ntohs(sin6->sin6_port));
}